Azo dyes and their production



Patented Nov. 7, i933 1,933,585 AZO DYES AND THEIR PRODUCTION Rainald Brightman and William Leslie Baber Wellacott, Blackley, Manchester, England, as-

signors to Imperial Limited, Westminister,

Chemical England Industries No Drawing. Application February 19, 1930,

Serial No. 429,810, and 5, 1929 in Great Britain March 11 Claims. (01. 260-85) According to this invention disazo dyes which have the valuable property of dyeing a regenerated cellulose rayon, as for example, viscose rayon, in even shades are obtained by tetrazotiz- 5 ing 3:3-diaminodiphenyl-urea or a substitution product thereof, other than a carboxylic or S111?- phonic acid derivative, and combining with 1 molecular proportion of a sulphonic or carboxylic acid of a phenol or a naphthol and one molecular proportion of a naphthylamine, naphthol or an N-substituted derivative of an aminonaphthol sulphonic acid; Alternatively we may obtain certain of the same dyestufis by coupling one molecular proportion of diazotized meta-nitroaniline. or a derivative thereof with carboxylic or sulphonic acid of a phenol or a naphthol or with an 'N-substituted naphthylamine sulphonic acid, reducing the nitro 'azo dyestufi and treatingwith carbonyl chloride the resultant aminoazo dyestuff, either lar proportion of another amino-azo dyestufi similarly prepared from diazotized meta-nitroaniline and another carboxylic or sulphonic acid derivative of a phenol or a naphtholor an N- substituted amino-naphtholor naphthylaminesulphonic acid. Further, we may obtain dyestuffs having the same or similar properties by replacing the m-nitroaniline by for instancem-aminoacetanilide or a derivative thereof, hydrolyzing- 3o the acylaminoazo dyestufi and treating with carbonylchlorfde the aminoazo dyestufi, either alone or in admixture with other aminoazo dyestuff as described above in the case of the diazotized mnitroaniline derivative.

The use or" certain disazo derivatives of 3:3- diaminodiphenyl urea as direct cotton colours has already been described, for instance, in specification E. P. 10,380/1913', in which is disclosed the manufacture of dsazodyes having affinity for 40 unmordanted cottonobtained by coupling a tetrazotized 3:3'- or 4:4-diaminodiphenylurea with one molecule of resorcinol and one molecule of an aminonaphthol sulphonic acid.

It is not disclosed, however, that in their behaviour in the dyeing of a regenerated cellulose rayon such as viscose rayon, there is the remarkable difierence in dyeing properties between the disazo derivatives of 3:3'-diaminodipheny1-urea and of 4:4-diaminodiphenylurea which we have 56 found in our experiments. Whereas the disazo derivatives of 4:4'-diaminodiphenyl-urea resemble the majority of substantive cotton dyeings in giving uneven dyeings on viscose rayon the disazo derivatives of 3:3-diaminodiphenylurea such as 5 are herein described possess the valuable property alone or mixed with an equi-molecuor" dyeing such as regenerated cellulose rayon in even shades. This invention is accordinglyof great value in the art of dyeing such fibres.

We have not described or claimed the dyes which may be derived 1 from tetrazotized 3:3- 60 diaininodiphenylurea and two molecular proportions of the same or different aminonaphthol sul phonic acds for we do not find these give the results described in the present invention. Thus the dyestuff obtained from one molecular proportion each of lt8-aminonaphtholi-sulphonic acid and 2 :8-aminonaphthol-6-sulphonic acid dyes viscose rayon uneven reddish violet shades.

The dyes of our invention may all be represented by the following generic formula to Rs N:N-R1 0:0

ITI N=NR2 H wherein R1 represents a coupled residue of a sulphonic or carboxylic acid derivative of a phenol or a naphthol, R2 represents a coupled residue of a naphthylamine, a naphthol, an N-substituted aminonaphthol sulphonic acid or an 'N-substi tuted naphthylarnine sulphonic acid, and R3 and R4 represent-hydrogen or a substituent suchas an alkoxy group.

The invention is illustrated by the following examples, to which it is not limited, the parts 9 being by weight.

" Example 1 242, parts of 3: 3'-diaminodiphenylurea are 9 tetrazotized with 138 parts of sodium nitrite and 500 parts of 36 per cent hydrochloric acid. The tetrazo solution is stirred into a cold solution containing 160 parts of sodium sallcylate and 600 parts of sodium carbonate. The coupling mixture. is stirred until combination is complete when there is run in a solution containing 239 parts or Z-amino-8-naphthol-6-sulphonit: acid. The mixture is maintained alkaline and after stirring to complete the coupling it is heated up and the dyestuff isolated by the addition of common salt. It dyes viscose rayon a yellowish brown shade. If in place of 239 parts of 2-ainino- 8-naphthol-6-sulphonic acid there is added'a solution containing 315 parts-of 2-phenyl-arhino- 8-naphthol-6-sulphonic acid there is obtained a dyestufi giving brown shades on viscose rayon.

Example 2 242 parts of 3:3-diaininodiphenylurea are tetrazotized with 138 parts of sodium nitrite and 500 parts of 36 per cent hydrochloric acid. The tetrazo solution is run into a cold, well stirred solution containing 224 parts of l-naphthol-isulphonic acid and 750 parts of sodium carbonate.

' The coupling mixture is stirred until combina- 138 parts of meta-nitroaniline. are diazotized with 250 parts of 36 per cent hydrochloric acid and 69 parts of sodium nitrite in the known manner. The diazo solution is stirred into a well cooled solution or" 138 parts of salicylic acid in 40 parts of sodium hydroxide containing 350 parts of sodium carbonate. After stirring until coupling is complete the mixture is heated up and a solution containing 360 parts of sodium sulphide crystals is added and stirring continued until reduction of the nitro azo dyestuff to aminoazo dyestufi is complete.

Simultaneously with the above operations the diazo solution obtained from a further 138parts of m-nitroaniline is combined with 320 parts of l :8 dihydroxynaphthalene-3 6-disulphonic acid (chromotropic acid) in the presence of about 400 parts of sodium carbonate and the nitroazo dyestuff thus obtained is reduced in like manner with a solution containing about 360 parts of sodium sulphide crystals.

The solutions of the two aminoazo dyestuifs are now mixed and neutralized, 300 parts of sodium acetate crystals are added and a slow streamof carbonyl chloride is passed into the mixture. Sodium hydroxide solution is added gradually to keep the mixture free from mineral acidity and when the conversion of the aminoazo dyes to the urea is complete, the current of carbonyl chloride is stopped and the mixture made alkaline. Upon heating up and adding common salt there separates a dyestuff which dyes viscose rayon a bluish red shade.

If in place of 138 parts of salicylic acid in the above example there are used 224 parts of 1- naphtholi-sulphonic acid and in place of 320 parts of l :8-dihydroxy-naphthalene-3 :6-disulphonic acid 3:5 parts of ,2-phenylamino-8- naphthol-S-sulphonic acid there is obtained a dyestufi dyeing a viscose rayon a brown shade.

The following tables illustrate further dyestuffs which may be obtained according to our invention.

Tetrazotized and Coupling component (1 11101. g gg g coupled with of each) rayon Salicylic acid 3 {1 amino -5 naphthol 7- sul' Maroon urea. s lp ip v d a my 10 am 3'3"d1ammdpheny1 {2-benzoylamino-5-naphthol-7- Orange r ulphonic acidi. Y n h oresotinic aci e owis 3'al'dmmmodlphenyl {2-benzoylamino-8-naphthol fipink urea sulphonic acid.

Diazotized and coupled with Coupling mp nent m-aminoacetanilidehydrolyze m-nitroanilinel. 2-phenylamino-5-naphthol-7- 2- napl1tliol-7sulphonic acid, Pliosgenated Brownishsulpbonic acid, reduced. red 4-nitro-2-an1sid1ne Salicylic acid, reduced Phosgenated m-aminoacetanilide 2-phenylalnino-S-naphthol-(S- Brown sulphonic acid, hydrolyzed. 4-nitro-2-anisidine 2-naphthol-7-sulphonic acid, Phosgenatcd reduced.

Reddisli-violet wherein R1 represents a coupled residue of an azo dye coupling component selected from the class-consisting of mono-hydroxy-ben2enes and naphthols having a sulphonic or carboxylic acid group substituted thereon, R2 represents a coupled residue of an azo dye coupling component selected from the class consisting of 2-amino- 8naphthol- G-sulphonio acid, 2-pheny1amino-8enaphthol6- sulphonic acid, 2-phenylamino-5-naphtho1-7-sulphonic acid, l:8-dihydroxy-naphthalene-3 6-disulphonic acid, 1-an ino 5enaphthol-l-sulphonic acid, 2 benzoylamino-S-naphthol 7 sulphonic acid and 2-benzoylamino-8-naphthol-6-sulphonic acid, and R3 and R4 represent hydrogen or an alkoxy group.

2. As new products, the disazo dyes which are capable of dyeing regenerated cellulose materials in even level shades and which may be represented by the probable'formula wherein R1 represents a coupled residue of an azo dye coupling'component selected from the class consisting of salicylic acid, 1-naphtho1-4-.

sulphonic acid, 2-phenylamino8-naphthol-6-sulphonic acid, 2-phenylamino-5-naphthol-7sul phonic acid, 1 8-dihydroxy-naphtha1ene-3 6-disulphonic acid, l-amino-5-naphthol-7-sulphonic acid, 2 benzoylamino 5 naphthol-7-sulphonic acid and 2 benzoylamino 8 naphthol-6-sul- V in even level shades which may be represented capable of dyeing regenerated cellulose in even level shades which may be represented by the probable formula 1 phonic acid, and R: and R4 represent hydrogen or an alkoxy group, the said dyes dyeing regenerated cellulose in even level shades varying from brown to bluish-red. 1

3. As new products, the disazo dyes which are capable of dyeing regenerated cellulose. materials in even level shades and which may be represented by the probable formula R3 H R4 N- N: R; c =0 wherein R1 represents the coupled residue of salicylic acid, R2 represents the coupled residue 1 of 2ephenylamino-8 naphthol-6-sulphonic acid, H R and R3 and R4 represent hydrogen or a methoxy group, the said dyes dyeing regenerated cellulose inbrown shades.

7. As a new product, the ,disazo dye which is capable of dyeing regenerated cellulosein even level shades which may be represented by the probable formula wherein R1 represents the coupled residue of salicylic acid, R2 represents a coupled residue of an azo dye coupling component selected from the class consisting of 2-amino-8-naphthol-6- sulphonic acid, 2-phenylamino-8naphthol-6-sulphonic acid, 2-benzoylamino-5-%naphthol-'7-sulphonic acid, 1 amino 5 naphthol-l-sulphonic acid and 1:8-dihydroxy-naphthalene-3:6-disul- N- N=NR, phonic acid, and R3 and R4 represent hydrogen or a methoxy group, the said dyes dyeing re- I generated cellulose in even level shades varying f N from brown to bluish-red. H

4. As new products, the disazo dyes which are capable of dyeing regenerated cellulose materials I V wherein R1 represents the coupled residue of salicylic acid and R2 represents the coupled residue of 2-phenylamino-8-naphtho1-6-sulphonic acid; the said dye dyeing regenerated cellulose by the probable formula H R3 in brown shades.

| 8. As new products, disaZo dyes which are ca- /N N=N-R1 pable of dyeing regenerated cellulose in even level shades and which may be represented by the probable formula: i r r OW O H0 0 wherein R1 represents the coupled residue of N= salicylic acid, R2 represents the coupled residue of a 2 amino 8 naphthol 6 sulphonic acid or 2- Hoas/ V phenylamino-8-naphthol-6-sulphonic acid, and Rs and R4 represent hydrogen or an alkoxy group, the said dyes dyeing regenerated cellulose in yellowish-brown to brown shades.

5. As a new product, the disazo dye which is capable of dyeing regenerated cellulose in even level shades which may be represented by the probable formula wherein-R1 represents the coupled residue of an azo dye coupling component selected from the class consisting of salicylic acid, o-cresotinic acid,

I-sulphonic acid and R5 represents a phenyl or benzoyl group, said dyes dyeing regenerated cellulose in brown to bluish-red shades.

9. As new products, disazo dyes which are capable of dyeing regenerated cellulose in even level shades and which may be represented by the probable formula: N N=N-Rr H H I'M N- N=N-Rz 11 H' I 0 l H N= N-Rs HOaS wherein R1 represents the coupled residue of salicylic acid and R2 represents the coupled residue of Z-amino-S-naphthol-S-sulphonic acid, the said dye dyeing regenerated cellulose in yellowish-brown shades.

6. As new products, the disazo dyes which are wherein R1 represents the coupled residue of an azo dye coupling component selected from the class consisting of salicylic acid, 1-naphthol-4- sulphonic acid, and o-cresotinic acid and R5 a phenyl or benzoyl group, said dyes dyeing rel-naphthol-l-sulphonic acid, and 2-naphtholgenerated cellulose in brown to yellowish-pink cresotinicacld and R2 represents the coupled shades. residue of Z-benzoyl-amino-8-naphthol-6-sul- 10. As new products, disazo dyes which are caphonic acid, said dye dyeing regenerated cellupable of dyeing regenerated cellulose in even lose in yellowish-pink shades. level shades and which may be represented by the RAINALD BRIGHTMAN probable formula: --WILLIAM LESLIE BABER WELLACOTT.

0 7 R1-N=N N=N N- HOeS wherein Ri represents the coupled residue of an azo dye coupling component selected from the class consisting of salicylic acid and l-naphthol- 4-sulphonic acid, said dyes dyeing regenerated cellulose in brown shades.

11. As new products, disazo dyes which are capable of dyeing regenerated cellulose in even level shades and which may be represented by the probable formula:

II I Q H -Q 0 R1N=N v I N=NR2 wherein R1 represents a coupled residue of ortho- 

